Tourniquet with lever tensioning mechanism

ABSTRACT

A tourniquet includes: a baseplate with first and second ends; a strap having first and second ends, the strap having a first portion adjacent its first end, and a second portion adjacent its second end; a lever with proximate and distal ends, wherein the proximate end is pivotally connected to the baseplate, and the distal end is free; wherein the first end of the strap is pivotally connected to the lever intermediate to the proximal and distal ends; and a connector assembly operable to selectively connect the second portion of the strap to the baseplate, so as to form a closed loop, the connector assembly operable to permit a length of the closed loop to be adjusted.

BACKGROUND OF THE INVENTION

This invention relates generally to tourniquets and more particularly toself-applied tourniquets.

Tourniquets are known and used for stopping blood flow preventingmassive hemorrhage which can result in death. Massive hemorrhage remainsthe number one cause of preventable death on the battlefield despitecurrent tourniquet use. Catastrophic limb injuries are not unique to thebattlefield and can occur in the civilian sector with motor vehicleaccidents, industrial accidents, agricultural accidents and activeshooter episodes.

When a major blood vessel is cut, a short period of time is available tostop the flow of blood and prevent massive hemorrhage and ultimatelydeath.

It is helpful to provide a tourniquet that can be self-applied by theinjured person as medical personnel may not be readily available.Self-applied tourniquets are known and used in the art.

One problem with existing self-applied tourniquets is that they requirethe use of a winding stick, (or windlass), which is used to tension thetourniquet and occlude the arterial blood flow. The stick and otherparts of the tourniquet can protrude, catch on objects, become dislodgedfrom its locked position and at times not work. With the windlassdislodged, tourniquet effect is lost creating problems during transportand possibly demise. The windlass also adds weight and increases thebulk of the tourniquet, making it more difficult to store and to carry.

BRIEF SUMMARY OF THE INVENTION

This problem is addressed by a self-applied tourniquet utilizing a levertensioning mechanism.

According to one aspect of the technology described herein, a tourniquetincludes: a baseplate with first and second ends; a strap having firstand second ends, the strap having a first portion adjacent its firstend, and a second portion adjacent its second end; a lever withproximate and distal ends, wherein the proximate end is pivotallyconnected to the baseplate, and the distal end is free; wherein thefirst end of the strap is pivotally connected to the lever intermediateto the proximal and distal ends; and a connector assembly operable toselectively connect the second portion of the strap to the baseplate, soas to form a closed loop, the connector assembly operable to permit alength of the closed loop to be adjusted.

According to another aspect of the technology described herein, atourniquet includes: a baseplate with first and second ends, and a strapguide disposed at the first end; a strap having first and second ends,the strap having a first portion adjacent its first end, and a secondportion adjacent its second end, wherein the first portion of the strapis engaged with the strap guide; a lever with proximate and distal ends,wherein the proximate end is pivotally connected to the baseplate, andthe distal end is free; wherein the first end of the strap is pivotallyconnected to the lever intermediate to the proximal and distal ends,such that the lever is movable between released and tightened positions,wherein a free length of the strap extending beyond the baseplate isshorter in the tightened position than in the released position; alocking mechanism operable to secure the lever in the tightenedposition; and a connector assembly operable to selectively connect thesecond portion of the strap to the baseplate, so as to form a closedloop, the connector assembly operable to permit a length of the closedloop to be adjusted.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be best understood by reference to the followingdescription taken in conjunction with the accompanying drawing figures,in which:

FIG. 1 is a schematic perspective view showing an exemplary tourniquet;

FIG. 2 is an enlarged view of a portion of FIG. 1;

FIG. 3 is a schematic top plan view of a portion of an alternative straphaving a finger hole formed therein;

FIG. 4 is a schematic top plan view of a portion of an alternative strapincorporating cut markings;

FIG. 5 is a perspective view showing an alternative lever end;

FIG. 6 is a perspective view showing an alternative strap end;

FIG. 7 is a schematic side elevational view showing an alternativeembodiment of a baseplate with an integral pivot member;

FIG. 8 is a perspective view showing the baseplate and lever of FIG. 7;

FIG. 9 is a perspective view showing a baseplate and a strapincorporating a hook member;

FIG. 10 is a perspective view showing a baseplate and a strapincorporating a hook member;

FIG. 11 is a perspective view showing a baseplate and a strapincorporating an alternative hook member;

FIG. 12 is a perspective view showing a baseplate and a strapincorporating a snap buckle;

FIG. 13 is a perspective view showing a first step in using thetourniquet of FIG. 1, with the tourniquet being initially applied to thelimb of a patient;

FIG. 14 is a perspective view showing a second step in using thetourniquet of FIG. 1, with the strap being secured in a closed looparound the limb;

FIG. 15 is a perspective view showing a third step in using thetourniquet of FIG. 1, with a lever thereof being moved towards atightened position;

FIG. 16 is a perspective view showing a fourth step in using thetourniquet of FIG. 1, with the lever moved to a fully tightenedposition;

FIG. 17 is a perspective view showing a fifth step in using thetourniquet of FIG. 1, with the lever being secured in the fullytightened position;

FIG. 18 is a perspective view showing a sixth step in using thetourniquet of FIG. 1, with the excess strap being secured over thelever;

FIG. 19 is a schematic side elevational view showing an alternative,concave-curved baseplate in a first condition; and

FIG. 20 is a schematic side elevational view showing the baseplate ofFIG. 19 in a second condition;

FIG. 21 is a schematic side elevational view showing an alternative,ramped baseplate;

FIG. 22 is a schematic end view of a baseplate showing a latchmechanism; and

FIG. 23 is a perspective view showing a tourniquet constructed using analternative baseplate.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings wherein identical reference numerals denotethe same elements throughout the various views, FIGS. 1 and 2 illustratean exemplary tourniquet 10. The basic components of the tourniquet 10are a strap 12, a baseplate 14, and a lever 16, each of which will bedescribed in more detail below.

The strap 12 is an elongated flexible member extending continuouslybetween first and second ends 18, 20 respectively. For purposes ofreference the strap may be described as having a first portion 17adjacent the first end 18 and a second portion 19 adjacent the secondend 20. The strap 12 may be constructed from any material which isflexible and which is capable of withstanding a predetermined tensileforce sufficient to cut off (occlude) blood flow in a patient's limb.Nonlimiting examples of suitable materials for the strap 12 includefabric and other textiles, plastics, metals, and combinations thereof.The strap 12 may be configured as a flat, band-like material as shown ormay have another form, such as a tube, rope, or cable. In theillustrated example, the strap 12 comprises woven nylon webbing.

The strap 12 incorporates suitable releasable connectors 22. As usedherein the term “releasable” refers to a connection that can be coupledand uncoupled in ordinary use without damage to the connectors. In someaspects, the connection is releasable without resorting to the use oftools. By way of example and not of limitation, examples of releasableconnectors include buttons, snaps, stud-type snap fasteners, magnets, orhook-and-loop type fasteners (e.g., VELCRO). In the illustrated example,the strap 12 incorporates hook-and-loop type fasteners. These connectorsare configured such that the strap 12 may be coiled into a compactbundle and secured to itself. These connectors are further configuredsuch that the second portion 19 of the strap 12 may be folded over andattached to itself. For example, one face or side of the strap 12 mayincorporate a loop portion of a hook-and-loop fastener over all or apart of its area, and the opposed face or side of the strap 12 mayincorporate a combined hook and loop portion of a hook-and-loop fastenerover all or a portion of its area.

FIG. 3 illustrates examples of optional features which may be providedto make it easier to manipulate the second end 20 of the strap 12. Inone example, an area at the second end 20 of the strap 12 includes anend marking 21 such as words, letters, symbols, patterns or colors whichserve to make the second end 20 easily identifiable. In another example,the second end 20 may be provided with chamfered corners 23 to provide alead-in element for feeding the second end 20 through the slotsdescribed below. In another example, the terminal part of the second end20, for example about 19 mm (¾ in.) may be smooth and free of fastenersor other protrusions to facilitate easy grasping. A finger hole 24 maybe provided at or near the second end 20. The finger hole 24 may besized to permit use while wearing gloves.

The basic length of the strap 12 may be selected to permit use with arange of users and for different limbs. For example, the basic lengthmay be suitable to encircle the largest limb of the largest possibleuser. A user may choose to shorten the strap 12 to avoid excess lengthand to reduce weight, permitting easier storage and transport. Somemeans may be provided to make it easier to shorten the strap 12. Forexample, cut markings 26 indicating predetermined length intervalsand/or flat sections 28 configured to facilitate easy cutting with handtools (e.g., scissors, pocket knife) may be provided along the length ofthe strap 12, as seen in FIG. 4. The fibers within the flat sections 28may be consolidated (e.g. by thermal or ultrasonic bonding, adhesivesealing) so as to be resistant to fraying and unraveling after cutting;however, these sections otherwise retain the full strengthcharacteristics of the remainder of the strap 12. Optionally, the cutmarkings 26 could indicate specific lengths, for example the maximumpossible length required for use with a leg, or the maximum possiblelength required for use with an arm. Portions of the strap 12 near theflat sections 28 and/or cut markings 26 may be configured so that, aftercutting, the remaining portion provides one or more of the originaldistal end features, such as: an end marking, chamfered corners, asmooth, protrusion-free end, or a finger hole.

The baseplate 14 is a relatively thin, plate-like rigid or semi-rigidmember. Nonlimiting examples of suitable material for the baseplate 14include plastics, wood, metals, and combinations thereof. In theillustrated example, the baseplate 14 is constructed as a flat plate ofpolymeric material with a generally rectangular plan view shape.

Referring to FIG. 2, the baseplate 14 includes a strap guide 30 at afirst end 32 thereof (also referred to herein as an aft end). Thepurpose of the strap guide 30 is to permit axial movement of the strap12 relative to the baseplate 14, while preventing lateral movement ofthe strap 12 relative to the baseplate 14. In the illustrated example,the strap guide 30 comprises a slot formed near the first end 32 of thebaseplate 14 through which the first end 18 of the strap 12 is threaded.Other guide structures such as rails or flanges (not shown) could beused as an alternative.

The baseplate 14 includes a lever anchor 34. In the illustrated example,the lever anchor 34 comprises a closed loop 38 of nylon webbing or otherflexible material which is fed through the lever 16, and a pair ofclosely-spaced slots 40 formed in the baseplate 14. In the illustratedexample the lever anchor 34 is positioned at or near a second end 36 ofthe baseplate 14, opposite to the first end 32, but other locations arepossible.

The lever 16 is a substantially rigid member which is stiff enough toact as a lever. Nonlimiting examples of suitable material for the lever16 include metals, plastics, wood, composites, and combinations thereof.In the illustrated example, the lever 16 is constructed as a unitary ormonolithic metallic element having a pair of side rails 42interconnected by crossbars 44. The side rails 42 may be curved suchthat the lever 16 has an arcuate shape when viewed in side elevation.

The lever 16 includes a first pivot element 48 at a first or proximateend 50 thereof. The first pivot element 48 is connected to the leveranchor 34 such that the lever 16 can pivot relative to the baseplate 14,about a pivot axis “A” passing through the first pivot element 48. It isnoted that this axis A is shown merely for reference and that itsabsolute location may vary depending on the tension in the closed loop38. In the illustrated example, the first pivot element 48 is defined byone of the crossbars 44 which is captured by the closed loop 38 of thelever anchor 34.

The lever 16 is configured such that it can be manually pivoted aboutthe first pivot element, and may include a handle element 49 for thepurpose of providing leverage. In the illustrated example, the handleelement 49 is defined by another one of the crossbars 44 located at asecond or distal end 52 of the lever 16.

Optionally, the handle element 49 may be contoured or shaped to providea protruding portion for the purpose of making it easier to grip. Forexample, FIG. 5 illustrates a variation of a handle element 149 which iscurved outwards, defining a convex finger pull 150. This may beimplemented in conjunction with a modified lock tab 158 including acutout 160 to provide access to the finger pull 150.

The lever 16 includes a second pivot element 54 positioned in anintermediate location between the proximate end 50 and the distal end52. In the illustrated example, the second pivot element 54 is definedby another one of the crossbars 44. The first end 18 of the strap 12 isconnected to the second pivot element 54 such that the lever 16 canpivot relative to the strap 12. For example, the first end 18 of thestrap 12 may be wrapped around the second pivot element 54 and thensecured to itself using conventional stitching.

Optionally, the tourniquet 10 may incorporate a means for moving thefirst end 18 of the strap 12 to different positions between theproximate end 50 and the distal end 52. For example, FIG. 6 shows afirst end 18 of the strap 12 wrapped around a representative crossbar 44and secured to itself using heavy-duty snaps 45 or another similarreleasable fastener. The first end 18 could be moved by opening thesnaps 45, placing the strap and around a different crossbar, and thenre-securing the snaps 45. The effect of moving the first end 18 would beto change the mechanical advantage of the lever 16 on the strap 12, witha corresponding inverse effect on the displacement of the strap 12. Thisadjustment may be used to tailor the performance of the tourniquet 10 toan individual user's preference.

Collectively, the lever 16, baseplate 14, and strap 12 are assembledsuch that the lever 16 is movable in a pivoting motion about the pivotaxis A. Movement from the released position to the tightened positioncauses the first end 18 of the strap 12 to be drawn through the strapguide 30. This movement causes a free length of the strap 12, defined asan amount of the strap 12 extending beyond the perimeter of thebaseplate 14, to be reduced.

Alternative means may be provided for pivotal mounting of the lever 16.For example, FIGS. 7 and 8 illustrate an optional variation of thebaseplate 14 in which the closed loop 38 described above is eliminated,and one of the slots 40 is replaced by a rigid, generally U-shapedmember 51 which is formed as part of the baseplate 14 and which capturesthe first pivot element 48 of the lever 16.

Some means are provided for securing the lever 16 in the tightenedposition. In the example shown in FIG. 1, a lock tab 58 is provided inthe form of a strap of flexible material which is looped around thehandle element 48 of the lever 16. The lock tab 58 incorporates suitablereleasable connectors 60. The illustrated example shows a patch ofhook-and-loop fastener material.

Optionally, the lock tab 58 may incorporate one or more features to makeit easier to identify and/or manipulate, as described above for thesecond end 20 of the strap 12, for example, an end marking, chamferedcorners, a smooth, protrusion-free end, or a finger hole.

Alternatively, the lever 16 and/or the baseplate 14 may incorporate alatch or other similar mechanism operable to connect the lever 16 to thebaseplate 14, thereby securing the lever in the tightened position. Forexample, FIGS. 7, 8, and 22 illustrate a latch 59 comprising a pair ofspaced-apart generally L-shaped resilient hooks 61 with barbed tipsprotruding from the baseplate 14 near its second end 36. The hooks 61are positioned such that the lever 16 can pass around them when it ismoved to the tightened position. When the lever 16 reaches the fullytightened position the barbed ends of the hooks 61 engage it and preventit from being released. If there is a need to release the lever 16, forexample if arterial occlusion is not achieved, then the hooks 61 can bereleased by squeezing them together, or alternatively, the lever 16could be pulled up with sufficient force to disengage the hooks 61.

The tourniquet 10 includes a “connector assembly” operable toselectively connect the second portion 19 of the strap 12 to thebaseplate 14, so as to form a closed loop. The connector assembly isoperable to permit a length of the closed loop to be adjusted (i.e.,lengthened or shortened). It will be understood that the connectorassembly may be a discrete element, or it may be defined in whole orpart by the strap 12, the baseplate 14, or some combination thereof.

In the illustrated example, one of the slots 40 described above locatedat the second end 36 of the baseplate 14 accepts the second end 20 ofthe strap 12. The second portion 19 of the strap 12 can be passedthrough the slot 40, pulled to a desired position (i.e., adjusted), andthen folded back and connected to the remainder of the strap 12 usingthe releasable connector 22. This is an example of a “connectorassembly”.

Alternatively, the second portion 19 of the strap 12 may be connectableto the baseplate 14 using a hook-type connection wherein one of thebaseplate 14 and the strap 12 includes a female element, and the otherof the baseplate 14 and the strap 12 includes a complementary maleelement. For example, the second portion 19 of the strap 12 may have aflat hook 62 attached thereto as seen in FIG. 9, with a slot 64 thatpermits adjustment of the strap 12. The end of the flat hook 62 can inturn be engaged with one of the slots 40 of the baseplate 14. This isanother example of a “connector assembly”. Alternatively, a differentanchor may be provided for the end of the flat hook 62. For example,FIG. 10 shows a variation in which a ring 63 with a generallyrectangular shape and made of a rigid material such as metal or plasticis attached to the closed loop 38 of the lever anchor 34. In theillustrated example, the closed loop 38 is simply passed through thecenter of the ring 63. Alternatively, the ring 63 could be secured tothe closed loop 38 using stitching or some other fastening method (notshown) to force it to remain in a specific position. In use, the end ofthe flat hook 62 can be engaged with the ring 63. This provides a secureconnection point and prevents stresses on the baseplate 14, especiallythe slot 40.

FIG. 11 shows an example of another type of hook 162 that may beattached to the second portion 19 of the strap 12. The hook 162 includesa slot 164 that permits adjustment of the strap 12. The hook 162 has agenerally S-shaped body that defines two separate, parallel engagementslots 166, 168 that are open at opposite sides of the hook body. Eitherof the engagement slots 166, 168 can be engaged directly with the closedloop 38. This avoids fatigue on the baseplate 14, and permits use fromeither direction (left or right). This is another example of a“connector assembly”.

Alternatively, as seen in FIG. 12, the second portion 19 of the strap 12may have a first half 66 of a known type of connector such as a snapbuckle 68 attached thereto, and the second half 70 of the snap buckle 68may be attached to the second end 36 of the baseplate 14. The two halvesof the snap buckle 68 may be engaged by pushing them together, and maybe separated by depressing the tang 72 of the first half 70. The firsthalf 70 includes a slot 74 that permits adjustment of the strap 12. Thisis yet another example of a “connector assembly”. The snap buckle 68 (orany of the connector assemblies described above) may be attacheddirectly to the baseplate 14, or by using an intervening strap 69.

Optionally, the tourniquet 10 may incorporate a counter-pull handle,defined as an element which permits a user to grasp and pull the firstend 32 of the baseplate 14. In the example shown in FIG. 8, acounter-pull handle 76 comprises a loop of cord with distal ends 78 fedthrough holes 80 in the baseplate 14 and secured by ferrules 82.

The use of the tourniquet 10 will now be described with reference toFIGS. 13-18. In these figures, the tourniquet 10 is being shown appliedto a limb “L” which happens to be a user's thigh; however, it will beunderstood that the usage steps are similar for any limb.

It is noted that the tourniquet 10 may be stored in a compactconfiguration by coiling the strap 12 around the baseplate 14 and usingthe releasable connector 22 of the strap 12 to secure the strap 12 inthe coiled configuration. Before carrying out the following steps, thetourniquet 10 would be retrieved and the strap uncoiled to prepare itfor use. Alternatively, the tourniquet 10 may be used as a belt bywrapping the strap 12 around a user's torso and using the releasableconnector 22 of the strap 12 to secure the strap 12.

Referring to FIG. 13, use begins by placing the tourniquet 10 with thebaseplate 14 against the limb L. If the end of the limb L is free, thesecond portion 19 of the strap 12 may be pre-looped through the slot 40in the baseplate 14, or the flat hook 62 or snap buckle 68 describedabove may be pre-connected. Then the entire tourniquet 10 already formedin a closed loop may be slipped over the free end of the limb L andmoved into position. However, there may be circumstances where this isundesirable or impossible. For example, a user's foot may be trappedunderneath a vehicle or building rubble. Under such circumstances, thesecond portion 19 of the strap 12 would initially be disconnected fromthe baseplate 14. After bringing the second portion 19 around the limbL, the second portion 19 of the strap 12 would then be connected to thebaseplate 14, i.e., by using the slot 40, the flat hook 62, or the snapbuckle 68 as provided.

In a second step, shown in FIG. 14, the second portion 19 of the strap12 is wrapped around the body of the strap 12 and is pulled taut inorder to remove the majority of the slack from the strap 12. The term“majority of the slack” refers to pulling the strap 12 sufficiently tautso that operation of the lever 16 will tighten the strap 12 enough tocut off blood flow to the limb L. The exact tension to be used willdepend on the specific user. The user may be trained or provided withinstructions as to how to properly remove the majority of the slack. Thestep of removing the majority of the slack may also be referred to aspre-tensioning the tourniquet 10. If the optional counter-pull handle 76is used, the user may pull this in opposition to the pulling tautmotion, either to make this step easier or to prevent unwanted movementof the tourniquet 10 relative to the limb L. The lever itself 16 couldalternatively be used for this purpose.

Once the slack is pulled out, the strap 12 is connected to itself inorder to form (collectively with the baseplate 14) a closed loop aroundthe limb L. The connection may be accomplished using the releasablefasteners 22.

In a third step, shown in FIG. 15, the lever 16 is pivotally actuated bymoving it from the released position towards the tightened position, asshown by the arrow in the figure. This may be done, for example bypulling sharply on the lock tab 58 or the lever 16, itself, in acontinuous motion. As the lever 16 is pivotally actuated, the first end18 of the strap 12 is drawn through the strap guide 30, whilesimultaneously the lever 16 applies tension to the lever anchor 34. Theoverall effect is to shorten the length of the closed loop formed by thebaseplate 14, the lever 16, and the strap 12, thus supplying clampingpressure to the limb L and cutting off blood flow in the blood vessel.The strap guide 30 helps prevent the strap 12 from becoming twisted ormisaligned during the tightening operation.

If the optional counter-pull handle 76 is used, the user may pull thisopposite to the pivoting movement of the lever 16, either to make thisstep easier or to prevent unwanted movement of the tourniquet 10relative to the limb L. FIG. 16 shows the lever 16 in the fullytightened position.

Once the lever 16 has been pivotally actuated, it may be secured in thetightened position. For example, FIG. 17 shows the lock tab 58 connectedto the strap 12 using the releasable fastener 60, engaging releasablefasteners 22 of the strap 12. This prevents the lever 16 from moving outof the tightened position. It is noted that the lever 16 has anover-center motion, and so only a small amount of force is required tohold it in the tightened position, even though the tourniquet 10 may beapplying a very high clamping force.

Once the tourniquet 10 has been applied and the lever 16 secured by thelock tab 58, the free end of the strap 12 may be wrapped around the bodyof the tourniquet 10, covering the baseplate 14, lever 16, and lock tab58, and secured to the lock tab 58, as shown in FIG. 18. Thus secured,it performs a function of cutting off blood flow, with a very smallexterior profile and no protruding exterior element that could protrude,catch on objects, or become dislodged from its locked position, limitingthe user's mobility and possibly causing additional injury.

The baseplate 14 may not be completely rigid and therefore will tend tobend in a convex shape, conforming to the curvature of the limb L, whenthe tourniquet 10 is applied. It is possible under some circumstancesthat the corners or edges of the baseplate 14 might tend to causepinching of the limb L. This possibility may be addressed with the useof a baseplate which is concave-curved in a resting state. FIG. 19 showsa baseplate 114 with this concave curvature. This may be substituted forthe baseplate 14 described above. Thus curved, the baseplate would bespaced away from the limb L and would not tend to pinch. When thetourniquet 10 is applied and tightened, the baseplate 114 would tend toflatten out to a deflected shape is shown in FIG. 20. As another optionto address potential pinching, the center of baseplate may be flat, andthe distal ends of the baseplate may be bent at an angle, curved, orotherwise displaced, in a direction towards the lever 16. These endshave a similar effect in preventing pinching to the curvature describedabove. This feature may be referred to as the distal ends being“ramped”. FIG. 21 shows a baseplate 214 with ramped ends 215.

Several of the features of the tourniquet 10 described above can beintegrated into the baseplate in order to simplify its construction. Forexample, FIG. 23 illustrates a tourniquet 310 constructed using analternative baseplate 314 along with a strap 12 and lever 16 asdescribed above.

The baseplate 314 is a relatively thin, plate-like rigid or semirigidmember. Nonlimiting examples of suitable material for the baseplate 314include plastics, wood, metals, and combinations thereof. In theillustrated example, the baseplate 14 is constructed as aninjection-molded polymeric component with a generally rectangular planview shape. It has first and second ends 332, 336, respectively, andthese ends may be ramped as described above.

The baseplate 314 includes a strap guide 330 in the form of a slotformed near the first end 332 of the baseplate 314. The first portion 17of the strap 12 is threaded through the strap guide 330.

The baseplate 314 includes an integral lever anchor 334 between thefirst and second ends 332, 336. In the illustrated example, the leveranchor 334 comprises a resilient flange 338 formed integrally with thebody of the baseplate 314.

As used herein, the term “integral” refers to components whichfunctionally and/or physically form part of a unitary or monolithicwhole. For example, components which are machined from a single piece ofmaterial, formed as part of an additive manufacturing process, or formedas part of an injection molding process may be considered physically andfunctionally integral, unitary, or monolithic. As another example,separate components which are securely attached to each other by meanssuch as fasteners, mechanical joints, thermal or sonic bonding, oradhesives, may be considered functionally integral, unitary, ormonolithic.

The flange 338 is shaped so as to define a transverse channel 339 whichcaptures the first pivot element 48 of the lever 16. The flange 338 maybe constructed so as to lie tightly against the surface of the baseplate314, and may include an upturned lead-in feature 340 at its distal end.This facilitates initial assembly, by permitting the lever 16 to beforced between the flange 338 and the baseplate 314. Once the leverenters the channel 339, the flange 338 snaps back into place against thesurface of the baseplate 314, and strongly resists removal of the lever16.

In the illustrated example, a resilient hook 362 is integrally formed aspart of the baseplate 314, positioned at or near the second end 336. Thehook 362 may be constructed so as to lie lightly against the surface ofthe baseplate 314, and may include an upturned lead-in feature 364 atits distal end.

A ring 365 with a generally rectangular shape and made of a rigidmaterial such as metal or plastic is attached to the second portion 19of the strap 12. The ring 365 includes a first slot 367 which is sizedto fit the strap 12 with a relatively “tight” (e.g., friction) fit. Theexposed portion of the ring 365, and a second slot 369, are collectivelysized to fit the hook 362. In the illustrated example, the strap 12 issimply passed through the first slot 367. In use, the end of the ring365 can be engaged with the lead-in feature 364 and then pulled intofull engagement with the hook 362. The spring tension inherent in thehook 362 is made sufficiently light that the ring 365 can be easilyremoved if necessary.

Once the ring 365 is engaged in the hook 362, the second portion 19 ofthe strap 12 can be pulled to a desired position (i.e., adjusted), andthen folded back and connected to the remainder of the strap 12 usingthe releasable connector 22. The combined structure of the hook 362 andthe ring 365 is another example of a “connector assembly”.

The baseplate 314 may optionally incorporate a latch or other similarmechanism (not shown) similar to the latch 59 described above.

The baseplate 314 may incorporate a slot 337 at or near the second end336. This is similar to the slots 40 described above, and may be used asan alternative to the hook 362 to connect the second portion 19 of thestrap 12, in the manner described above.

This version of the baseplate 314 provides for simplified constructionand lower parts count. The basic usage of the tourniquet 310 issubstantially similar to that of the tourniquet 10 described above.

The tourniquet described above has numerous advantages over pre-existingtourniquets. For example, the tourniquet is of a lighter weight, is amore compact package for easier storage, is easily and more rapidlyapplied by a user, and has no protruding portions which could limit theusers range of motion, become caught on objects and or become dislodgedfrom its locked position rendering the device useless.

The foregoing has described a tourniquet. All of the features disclosedin this specification (including any accompanying claims, abstract anddrawings), and/or all of the steps of any method or process sodisclosed, may be combined in any combination, except combinations whereat least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanyingclaims, abstract and drawings) may be replaced by alternative featuresserving the same, equivalent or similar purpose, unless expressly statedotherwise. Thus, unless expressly stated otherwise, each featuredisclosed is one example only of a generic series of equivalent orsimilar features.

The invention is not restricted to the details of the foregoingembodiment(s). The invention extends to any novel one, or any novelcombination, of the features disclosed in this specification (includingany accompanying claims, abstract and drawings), or to any novel one, orany novel combination, of the steps of any method or process sodisclosed.

What is claimed is:
 1. A tourniquet, comprising: a plate-like baseplatewith first and second ends, the baseplate having a strap guide disposedat the first end; a strap having first and second ends, the strap havinga first portion adjacent its first end, and a second portion adjacentits second end, wherein the first portion is engaged with the strapguide; a lever with proximate and distal ends, wherein the proximate endis pivotally connected to the baseplate, and the distal end is free;wherein the first end of the strap is pivotally connected to the leverintermediate to the proximal and distal ends; a connector assemblyoperable to selectively connect the second portion of the strap to thebaseplate, so as to form a closed loop, the connector assembly operableto permit a length of the closed loop to be adjusted; and wherein thefirst and second ends of the baseplate are both ramped towards thelever, in a configuration which would create a space between a limb andthe first and second ends of the baseplate, when the baseplate is placedagainst the limb prior to tightening of the tourniquet.
 2. Thetourniquet of claim 1 wherein the strap guide comprises a slot formed inthe first end of the baseplate through which the first portion of thestrap is threaded.
 3. The tourniquet of claim 1 wherein the lever ismovable between released and tightened positions, wherein a free lengthof the strap extending beyond the baseplate is shorter in the tightenedposition than in the released position.
 4. The tourniquet of claim 1wherein the second portion of the strap includes a releasable connectoroperable to selectively connect the second portion of the strap to theremainder of the strap.
 5. The tourniquet of claim 1 wherein theconnector assembly includes: a slot formed in the baseplate sized toreceive the strap; and a releasable connector disposed on the strap andoperable to selectively connect the second portion of the strap to theremainder of the strap.
 6. The tourniquet of claim 1 further comprisinga locking mechanism operable to secure the lever in the tightenedposition.
 7. The tourniquet of claim 1 further comprising a latchcarried on the baseplate operable to engage the lever in the tightenedposition.
 8. The tourniquet of claim 1 further comprising a lock tabcarried at the distal end of the lever.
 9. The tourniquet of claim 8wherein the lock tab includes a releasable connector operable toselectively connect the lock tab to the strap.
 10. The tourniquet ofclaim 1 wherein the baseplate includes a lever anchor comprising aclosed loop of flexible material which surrounds a pivot element of thelever.
 11. The tourniquet of claim 1 wherein the baseplate includes alever anchor comprising a rigid U-shaped element which surrounds a pivotelement of the lever.
 12. The tourniquet of claim 1 wherein the levercomprises a pair of spaced-apart side rails interconnected by aplurality of crossbars.
 13. The tourniquet of claim 1 wherein thebaseplate has a concave curvature.
 14. The tourniquet of claim 1 whereina finger hole is formed in the second end of the strap.
 15. Thetourniquet of claim 1 wherein the strap comprises a plurality ofspaced-apart flat sections configured to facilitate cutting.
 16. Thetourniquet of claim 1 wherein the strap comprises a plurality ofspaced-apart cut markings.
 17. The tourniquet of claim 1 wherein acounter-pull handle is disposed at the first end of the baseplate. 18.The tourniquet of claim 1 wherein: the baseplate includes an integrallever anchor disposed between the first and second ends of thebaseplate, the lever anchor receiving the proximate end of the lever;and an integral resilient hook positioned at or near the second end ofthe baseplate; and a ring sized to fit the hook is attached to thesecond portion of the strap.
 19. The tourniquet of claim 18 wherein thelever anchor comprises a resilient flange shaped so as to define atransverse channel which captures a first pivot element of the lever.20. A tourniquet, comprising: a plate-like baseplate with first andsecond ends, and a strap guide disposed at the first end; a strap havingfirst and second ends, the strap having a first portion adjacent itsfirst end, and a second portion adjacent its second end, wherein thefirst portion of the strap is engaged with the strap guide; a lever withproximate and distal ends, wherein the proximate end is pivotallyconnected to the baseplate, and the distal end is free; wherein thefirst end of the strap is pivotally connected to the lever intermediateto the proximal and distal ends, such that the lever is movable betweenreleased and tightened positions, wherein a free length of the strapextending beyond the baseplate is shorter in the tightened position thanin the released position; a locking mechanism operable to secure thelever in the tightened position; a connector assembly operable toselectively connect the second portion of the strap to the baseplate, soas to form a closed loop, the connector assembly operable to permit alength of the closed loop to be adjusted; and wherein the first andsecond ends of the baseplate are both ramped towards the lever, in aconfiguration which would create a space between a limb and the firstand second ends of the baseplate, when the baseplate is placed againstthe limb prior to tightening of the tourniquet.
 21. The tourniquet ofclaim 20 wherein the second portion of the strap includes a releasableconnector operable to selectively connect the second portion of thestrap to the remainder of the strap.
 22. The tourniquet of claim 20wherein the connector assembly includes: a slot formed in the baseplatesized to receive the strap; and a releasable connector disposed on thestrap and operable to selectively connect the second portion of thestrap to the remainder of the strap.
 23. The tourniquet of claim 20further comprising a lock tab carried at the distal end of the lever,the lock tab including a releasable connector operable to selectivelyconnect the lock tab to the strap.
 24. The tourniquet of claim 20wherein the baseplate includes a lever anchor which surrounds a pivotelement of the lever.
 25. The tourniquet of claim 20 wherein thebaseplate has a concave curvature.
 26. The tourniquet of claim 20wherein: the baseplate includes an integral lever anchor disposedbetween the first and second ends of the baseplate, the lever anchorreceiving the proximate end of the lever; and an integral resilient hookpositioned at or near the second end of the baseplate; and a ring sizedto fit the hook is attached to the second portion of the strap.
 27. Thetourniquet of claim 26 wherein the lever anchor comprises a resilientflange shaped so as to define a transverse channel which captures afirst pivot element of the lever.